The research program will be focused in several program areas: effects of low-level long-term exposure to environmental agents. multiple-factor interactions, environmental cancer, asbestos-associated disease, biological properties of inorganic microparticles, halogenated hydrocarbons and related chemicals, toxic metals such as lead, arsenic and cadmium, immunobiology, and concomitantly, approaches to public health control. In this we are primarily concerned with human health effects and utilize population studies as an essential methodological approach, with interdigitation of epidemiological, clinical, biological and physical sciences. Because of the recognized need to consider the magnitude of the problems studied, environmental evaluation is included to provide quantitative information concerning dose-disease response relationships. We are particularly interested in environmental alterations which affect large numbers of people in environmental circumstances; for example, new research will be devoted to health effects of toxic chemical waste disposal, chemical contamination of public water supplies, and the consequences of asbestos exposure in schools and public buildings. Cooperative studies with occupational groups and identified populations in the general community subject to specific exposures, provide an effective approach to such research aims and serve further to build the application of information into the process of seeking the data. Too, such investigations serve to identify groups of people which have been exposed to these agents, i.e., high risk groups. Surveillance becomes feasible, and increases the possibility of discovering physiological changes and biological markers, their predictive significance and, ultimately, of risk modification and risk reversal.